Governing device for pumps



May 5,1925. 1,536,697

0. WECHSBERG GOVERNING DEVICE FOR ruurs Filed Au '29, 1921 I o I Nagllll l lmu :\\\\\\\\QJ gggg |||||1 11 a,

Patented May 5, 1925.

UNITED STATES 1,536,697 PATENT OFFICE.

' OTTO WECHSBERG, OF WORCESTER, MASSACHUSETTS, ASSTGNOR T COPPUS ENGI-NEERING AND EQUIPMENT COMPANY, OF WORCESTER, MASSACHUSETTS, A. COR-PORATION OF MASSACHUSETTS.

GOVERNING DEVICE FOR PUMTS.

Application filed August 29, 1921. Serial No. 496,270.

. citizen of the United States, residing at tolnatically reducedto onehundred pounds,

WVorcester, in the county of Worcester and Commonwealth .ofMassachusetts, have in vented a new and useful Improvement in aGoverning Device for Pumps, of which the following, together with theaccompanying drawings, is a specification.

My invention relates to governing devices for pumps commonly employedfor supplying water to steam boilers andv has for its object to providean improved governing device whereby the pump used in connectiontherewith is always adapted to deliver feed water to a boiler at apressure which exceeds the boiler pressuraby a predetermined amount.

Such governing devices, as described above, are commonly known as excesspressure pump governors and generally comprise a valve operated by apressure responsive device, such as a diaphragm or plunger, one side. ofwhich is subjected to the pressure of the boiler and a spring, and

the other side of which is subjected to the pressure of the waterdelivered to the boiler by the pump. This valvecontrols the admission ofsteam to the prime mover driving the pump and so operates as to causethe pump to be driven at such a speed that the pressure of the waterdelivered to the boiler substantially equals the ressure of the boilerplus the pressure 0 the spring. In other words, if the boiler pressureis, for instance, one hun'dred pounds and the spring so adjusted as togive an excess pressure of ten pounds, the pressure of the pump"discharge will be one hundred and ten pounds. If the boiler pressuredrops to ninety pounds, the feed water pressure will be auwith the samesetting of the spring of the governor.

It has been found that excess pressure whereupon the valve will open tosuch an ex: tent that the pump will be driven at a dangerously highspeed, inasmuch as it is operating with substantially no load. In orderto prevent such occurrences, it has been customary to employ 'anauxiliary governing device operating in connection with the excesspressure governor, such for example, as a valve which is normally keptopen against the pressure of a spring and which is adapted to shut offthe steam to the pump should the pressure fall below a predeterminedminimum value.

By my invention, I propose to do away with the necessity of using suchan auxiliary device in connection with the governor, by so constructinthe governor that it will itself automatlcally shut off the steam supplyto the prime mover driving the pump should thepump pressure fall below apredetermined minimum value. These and other advantageous features of myinvention will hereinafter more fully appear, reference being had to theaccompanying drawings, in which- I j Fig. 1 is a View in side elevationof a portion of a steam boiler showing a feed water pump connectedthereto and adapted to be controlled by my improved governor.

Fig. 2 is a transverse sectional view of a governor constructed inaccordance with my invention.

Like reference characters refer to like parts in the different figures.

Referring to Fig. 1, a steam boiler 1, of any ordinary construction, isadapted to be supplied with water through a feed pipe'2 leading from thedischarge outlet 3 of a pump i. .The pump 4 is connected to a primemover 5 which is adapted to'be supplied with steam from the boiler 1through a supply pipe 6 connected to the steam-line 7 of the boiler 1.prime mover 5 may be of any suitable type, either reciprocating orrotating, although both are shown for purposes of illustration as beingof the centrifugal type.

An excess pressure governor 8 is provided for controlling the admissionof steam to the prime mover 5 and,-as best shown in Fig. 2, generallycomprises a cylindrical body 9, at the top of which is formed a valvechamber 10. The ends of the valve chamber 10 are open and are connectedin the steam sup- The pump 4 and the ply pipe 6, as shown in Fig. 1. Amovable valve member 11 is located'in the valve chamber 10 and isprovided with a plurality of disks 12, 13, 14 and 15, which are adaptedto cooperate with the ports 16 and 17 provided in a wall 18 surroundingthe inlet opening 10 of the Valve chamber 10. The valve 11 is mounted ona stem 19 which extends downwardly through an opening 9 in the body 9and terminates in a head 20, to which is secured a suitable pressureresponsive member, such as a flexible diaphragm 21. A portion of thestem 19 .is threaded, as shown at 22, to receive a nut 23 and a spring24 surrounds the stem 19 between the nut 23 and an annular projection 25extending inwardly from the wall of the body 9.

A flange 26 is provided at the lower end of the valve body 9, ofsomewhat greater diameter than the diaphragm 21, and a diaphragm cap 27,removably secured to the flange 26, is adapted to clamp the outerperiphery of the diaphragm 21 to the flange 26. An opening 28 isprovided in the flange 26 for receiving a pipe 29 which is connected tothe steam supply pipe 6 between a manually operated valve 30 and theinlet opening 10 of the valve chamber 10. The diaphragm cap 27 isprovided with an opening 31 for receiving a pipe 32 which is connectedto the discharge outlet 3 of the pump 4. The diaphragm cap 27 is furtherprovided with a centrally located threaded opening 33 within which isreceived a lifting screw 34, provided at one end with a tool receivingportion 35, by means of which it may be turned in the opening 33. Theupper end of the screw 34 is provided with an enlarged head 36 whichfits tightly in a countersunk portion 37 of the opening 33. A washer 38preferably composed of some wear resistant material, such as leather orfibre, is secured to the top of the head 36, for the purpose ofpreventing wear on the lower surface of the diaphragm 21 when thelifting screw 34 is turned into contact therewith.

From the foregoing it is apparent that when the pump 4 is not running,the pressure of the sprin 24 will exert suflicient force upon the valvestem 19 to cause the valve disks 12 and 14 to beseated in the ports 16and 17 and thereby prevent the passage of steam through the valve chamber 10 even if the valve 30 were to be open.

Therefore, in order to start the pump, it is first necessary to turn thelifting screw 34 into the cap 27 until the washer 38 engages thediaphragm 21 and lifts the stem 19 enough to move the disks 12 and 14out of the ports 16 and 17. The valve 30 may then be opened whereuponsteam will pass through the ports and the outlet opening 10 to the primemover 5 which will then start the pump 4. As soon as the pump starts tobuild up pressure in the feed pipe 2, the under side of the diaphragm 21will be subjected to the water pressure, and as the pump speeds up, thispressure will increase and tend to move the stem 19 upwardly against thecombined pressure of the steam and the spring 24. If the pressuredeveloped by the pump exceeds that on the upper side of the diaphragm21, the valve 11 will be moved upwardly far enough to cause the disks 13and 15 to be seated in the ports 16 and 17 and thereby tend to cut offthe steam supply to the prime mover 5. The pump pressure will then falluntil it is substantially the same as the combined pressure of the steamand the spring, whereupon the valve will move to a positioncorresponding to that shown in the drawings, in which the valve ports 16and 17 are midway between the disks 12 and 13, and 14 and 15,respectively, As long as this balanced condition exists, the diaphragm21 is substantially horizontal, as shown in Fig. 2. My improved devicewill then operate as the usual excess pressure pump governor to maintainthe pressure of the feed water above the boiler pressure a predeterminedamount, which is determined by the pressure exerted by the spring 24.Obviously this pressure may be adjusted by turning the nut 23 on thestem 19.

As soon as the pump is operating normally, as described above, thelifting screw 34 is turned out of the cap 27 to return it to itsoriginal position, as shown in Fig. 1, in which case the head 36 isagain received in thecountersunk opening 37 and prevents leakage of thewater under pressure through the opening 33. In case the pump operatorshould fail to turn out the screw 34 shortly after the pump isin-operation, his attention will be called to this fact by the leakageof water through the cap' caused by the fact that when the lifting screw34 is raised, the head 36 moves out of the countersunk opening 37 andwater may leak past the screw 34.

If at any time during the operation of the pump 4, the water supplyshould fail, it is obvious that the pressure in the pipe 32 would fallsubstantially to zero, whereupon the combined pressure of the steam andof the spring 24 acting on the upper side of the diaphragm 21 would movethe spindle 19 downwardly until the disks 12 and 14 are seated in theports 16 and 17, thereby completely cutting off the flow of steamthrough the valve chamber 10. The

the pipe. In other words, by the use of my improved governor, the pumpwill be caused to normally operate so that the pressure of the feedwater is always in excess of the steam pressure in the boiler by anamount determined by the setting of the spring 24, but upon theoccurrence of any interrup tion in the water supply or breakage in thefeed pipe, the pump will be automatically stopped before any damage hasbeen done.

The above described automatic stoppage of the pump is believed to be amost advantageous feature, for the reason that in the absence of thisfeature the pump would be liable to be operated at dangerously highspeeds whenever the pressure in the pipe 32 dropped to zero, owing tothe fact that the valve would be fully open. This is what has usuallyoccurred with excess pressure governors as heretofore constructed, andas previously pointed out, it has always been necessary to employ somesort of an auxiliary governing device in connection therewith, therebyadding considerably to the complication and cost of such installations.A governing device constructed in accordance with my invention combinesall the essential features necessary for normal and safe operationwithout adding appreciably to the complication of such devices ascompared with those previously constructed. While I have shown myinvention as applied to a particular type of governing device, it is notso limited, but is susceptible of such modifications as might benecessary to adapt it to other types of governing devices withoutdeparting from the spirit and scope of the invention, and I desire thatonly such limitations be imposed on the invention as come within thescope of the appended claims.

I claim: I

1. In apparatus of the class described, the combination with a steamboiler and a pump for supplying water thereto, of a governing device forcontrolling the operation of said pump so as to automatically maintainthe discharge pressure thereof a predetermined amount above the boilerpressure and to stop said pump should the discharge pressure fall belowa predetermined amount.

2. In apparatus of the class described, the combination with a steamboiler, a pump for supplying water thereto and a prime mover for drivingsaid pump, of a governing device'for automatically controlling thesupply of steam to'said prime mover so as to main tam the dischargepressure of said pump a predetermined amount above the boiler pressureand to shut 01f the supply of steam to said prime mover should thedischarge pressure fall below a predetermined amount.

3. In a governing device for steam pumps,- the combination with a sourceof steam supply, a steam driven water pump and a valve chamber providinga steam port located between said steam supply and said pump, of a valvemember responsive to the 'steam pressure and the water pressuredeveloped by said pump for closing said valve when the water pressureexceedsthe steam pressure a predetermined amount or when the waterpressure falls below a predetermined amount.

4. In a governing device for steam pumps,

the. combination with a source of steam sup- 1 ply, a steam driven waterpump and a valve chamber providing a steam port located bea valve memberprovided at one end with a plurality of spaced disks adapted to registerwith said port and provided at its other end with a diaphragm subjectedon opposite sides thereof to the steam pressure and to the waterpressure, and means for moving said valve member against thesteam'pressure in the absence of water pressure.

5. In a governing device for steam pumps, the combination with a sourceof steam supply, a steam driven water pump and a valvev chamberproviding a steam port located between said steam supply and said pump,of a valve member provided at one end with a plurality of spaced disksadapted to register with said port and provided at its other end with adiaphragm enclosed in a chamber .andsubjected on opposite sides thereofto the steam pressure and to the water pressure, the said valve memberbeing acted upon by a spring exerting its force in the same direction asthe steam and means for moving said valve member manually against thepressure of said spring.

6. In a governing device for steam pumps, the combination with a sourceof steam supply, a steam driven water pump and a valve chamber providinga steam port located between said steam supply and said pump, of a valvemember provided at one end with -aplurality of spaced disks adapted toregister with said port and provided at its other end with a diaphragmenclosed in a chamber and subjected on opposite sides thereof to thesteam pressure and to the water pressure, and a lifting screw locatedbelow said diaphragm and provided with a washer of wear resistantmaterial where it comes in contact with the lower surface ofsaiddiaphragm.

. 7 In a governing device for steam pumps,

the combination wlth a sourceof steam sup- 7 ply, a steam driven waterpump and a valve chamber providing a steam port located between saidsteam supply and said pump,

tween said steam supply and said pump, of

' and a lifting screw located below said diaphragm and adapted t6 permitthe passage of Water from the diaphragm chamber when said screw is movedinto engagement with 10 said diaphragm.

Dated this 19th day of August, 1921.

OTTO WVECHSBERG.

